What is the function of the organelle labeled C in the Diagram

The nucleus is responsible for storage as well as the transfer of genetic materials in the form of DNA or RNA.  It aids in the process of transcription by the synthesis of mRNA molecules and the nucleus controls the activity of all other organelles while facilitating processes like cell growth, cell division and synthesis of proteins.

Explanation:

The nucleus is a double membrane-bound structure responsible for controlling all cellular activities as well as a center for genetic materials, and it’s transferring.

It is the nucelus

Explanation:

the nucleus is the control center of the cell

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.